求助，用JQuery的append函数插入HTML代码无效

div.removeChild(img);
        var id = "#" + div.id;
        var divWidth = div.style.width;
        var width = divWidth.replace("px", "");
        var tbWidth = width - 8;
        var contentHTML = div.innerHTML;
        var viewHTML = "";
        var top =
        "<table border=\"0\" cellpadding=\"0\" cellspacing=\"0\" width=\"" + width + "px\">" + 
            "<tr>" + 
                "<td class=\"righttd1\"></td>" + 
                "<td class=\"righttd2\"></td>" + 
                "<td class=\"righttd3\"></td>" + 
            "</tr>" + 
            "<tr>" + 
                "<td class=\"righttd4\"></td>" + 
                "<td class=\"righttitletd\">" + 
                    "<table border=\"0\" cellpadding=\"0\" cellspacing=\"0\" width=\"" + tbWidth + "px\">" + 
                        "<tr>" + 
                            "<td style=\"width: 20px;\" align=\"center\">" + 
                                "<img src=\"/images/rightarealogo.gif\" width=\"10px\" height=\"10px\" />" + 
                            "</td>" + 
                            "<td align=\"left\">" + div.title + "</td>" + 
                        "</tr>" + 
                    "</table>" + 
                "</td>" + 
                "<td class=\"righttd5\"></td>" + 
            "</tr>" + 
            "<tr>" + 
                "<td class=\"righttd4\"></td>" + 
                "<td class=\"rightcontenttd\" style=\"width: " + tbWidth + "px;\">";
        var bottom =
                "</td>" + 
                "<td class=\"righttd5\"></td>" + 
            "</tr>" + 
            "<tr>" + 
                "<td class=\"righttd6\"></td>" + 
                "<td class=\"righttd7\"></td>" + 
                "<td class=\"righttd8\"></td>" + 
            "</tr>" +
        "</table>";
        div.title = "";
        $(id).prepend(top);
        $(id).append(bottom);我用这段代码往DIV前后插入HTML代码，但是在前面插入的可以显示，而在后面插入的却无法显示，希望高手帮忙！谢谢！